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The elevations of the data collected by Jason have been compared to elevation information <br />provided in the SL -07 Bond Release application. After the correction described above, all <br />elevation points were found to be between +/ -20 feet of the as -built elevations, shown on SL -07 <br />Exhibits 1, 2A, and 2B. Given the expanse of the mine site and the steepness of the terrain at <br />Colowyo, the difference in elevation is acceptable. <br />All of the measured and corrected elevations in the permanent post- mining drainage channels in <br />the SL -07 area were also +/- 20 feet of the elevations shown on the approved channel profiles. <br />Again, the difference in elevation is acceptable. <br />For both the East Pit area and the South Taylor Pit area, the Division finds that the Colowyo <br />Mine has achieved a post- mining surface that conforms to the approved post- mining topography <br />and resembles the general surface configuration of the land prior to mining. All highwalls have <br />been eliminated and the reclaimed lands blend in well with the adjacent undisturbed slopes. No <br />erosion problems were noted in the Phase I Bond Release areas, and no settling, slumping or <br />cracking of the backfill was observed. This is also true of the West Pit area, however other <br />issues were found as explained above. <br />Drainage Control <br />For the SL -07 bond release application, three ditches were inspected to determine if they were <br />constructed to meet the specifications in the PAP: the Final East Pit Ditch and the two ditches <br />that were constructed along the sides of the West Pit Fill. The side ditches are named West <br />Taylor West Tributary and West Taylor East Tributary in the PAP. Table 3 documents the <br />dimensions and rock sizes that were estimated during the May 21 inspection. All of the channels <br />were stable and met the specifications of the PAP or were somewhat larger (in terms of channel <br />dimensions or riprap size) than the specifications. <br />Other notable ditches near the SL -07 areas have not been built (West Pit Fill Ditch and Wet Pit <br />Coal Road Ditch in the West Pit area) or are not within the parcels in the application (the NTEP <br />Ditch is just outside the East Pit area). These ditches will not be Phase I released with SL -07. <br />Pond EP2 was found to have no problems, and it meets the specifications in the PAP, including a <br />spillway of approximately 15 feet in width. During the May inspection, the depth could not be <br />determined because the pond was full of turbid water. In a later inspection (July 9 — 10, 2013) <br />the depth was found to be sufficient: approximately 10 to 13 feet deep per the typical design <br />(Figure 2.05 -6 in PAP). <br />Summary and Conclusions <br />The Division has completed its review and evaluation of the SL -07 Phase I Bond Release <br />application submitted by Colowyo for the Colowyo Mine. The Division proposes a partial Phase I <br />Proposed Decision and Findings of Compliance August 2013 <br />Partial Phase I Bond Release SL -07 Page 7 <br />